Water-based fluids such as, for example, drilling fluids, milling fluids, mining fluids, water-based metal working fluids, food additives and water-based paints, are useful in a variety of industrial applications. It is well known to those skilled in the art of drilling wells to tap subterranean deposits of natural resources, such as gas, geothermal steam or oil, especially when drilling by the rotary method or the percussion method wherein cuttings must be removed from the bore hole, it is necessary to use a drilling fluid.
The use of water-based fluids in, for example, workover and completion fluids in oil field operations is also well known to those skilled in the art. Workover fluids are those fluids used during remedial work in a drilled well. Such remedial work includes removing tubing, replacing a pump, cleaning out sand or other deposits, logging, etc. Workover also broadly includes steps used in preparing an existing well for secondary or tertiary recovery such as polymer addition, micellar flooding, steam injection, etc.
Completion fluids are those fluids used during drilling and during the steps of completion, or recompletion, of the well. Completion operation can include perforating the casing, setting the tubing and pump, etc. Both workover and completion fluids are used in part to control well pressure, to stop the well from blowing out while it is being completed or worked over, or to prevent the collapse of casing from over pressure.
Additionally, many additives for water-based fluids were found to effectively provide fluid loss control, increase viscosity, inhibit drill solids, or combinations of two or more thereof, of the water-based fluids when the fluids are used in drilling a subterranean formation and contain little or no calcium chloride. However, as the calcium chloride concentration increases in the fluids, the effectiveness of these additives, especially for maintaining rheology and water loss control, decreases significantly. It is, therefore, highly desirable to develop an imnproved water-based fluid, or an additive thereof, and a process for using these fluids or additives.